Apparatus and process for flattening glass



Spt` 23, 1930. J. ARRAuL-r Er A1.'

APPARATUS AND PR u OCESS FOR FLATTENING GLASS Filed Aug. 21. 1926 @S KY WW .Nk

.WMA

IMHMNHJE refe' Patented Sept. 23, 1930 UNITE-n STATES PATENTE OFI-1c JULES ARRAULT AND LUCIEN DESHAMPS, 0F CHALON SUR-SAONE,` FRANCE, ASSIGN- ORS TO SOCIETE ANONYME DES MANUFACTURES'IDES GLACES & PRODUITS CHIM- IQUES DE SAINT-GOBAIN, CHAI'TNY & CIRZEY, 0F PARIS, FRANCE v t APPARATUS AND PROCESS FOR FLATTENING GLASS Application led August 21, 1926, Serial No. 130,676, and in France August 27, 1925.

,Sheetglassis commonly made by forming a cylinder, either manually, or automatically by the blowing or the drawing process, from molten glass. ,In the process of attening now generally employed these cylinders are then split longitudinally into one or mo-re segments, whichare reheated, and flattened by laying them upon a flattening stone, and rubbingtheir upper Vsurface with a suitable tool until fiat. This is a laborious operation as it requires for its successful completion skilled workers. Even then sheetsare frev quently more or less damaged. The upper surface of thesheet may be injured by the fiattening tool. The tool may also cause movement of the glass on the flattening stone, resulting in stria, particularly on the under surface, which moreover may have its finish impaired by inequality of the stone into which it is forced by the tool, or it may, if too ho-t, stick to the stone.

The object of the present invention is to overcome these defects present in flattening glass by the rubbing operation above described, and it involves the flattening of curved glass by tractive effort exerted thereon.

In carrying out our invention we exert a traction on two opposite generant lines of the cylinder of glass, so-that two flat sheets are formed, each connected with the other at its opposite side by acurved portion which may be afterwards out ofi' and rejected. This may be accomplished by hanging a cylinder of proper length while heated upon a bar carried on suitable supports and exerting tractive effort on the bottom ofthe cylinder by a second bar passing lengthwise therethrough and having attached to its projecting ends rods by which the traction may be exerted to aid in separating the rods.

Referring to the accompanying drawings in which corresponding parts are designated by similar marks of reference,-

Figure 1 is a longitudinal section through` an apparatus invented by us for carrying out our improved process'.

Figures 2, 3 and 4 are transverse sections on lines 17-17, 18-18 and 19-19 respectively of Figure 1.

after described.-

As shown, we provide a suitable heated structure divided into a plurality of compartments by means of sliding doors 54, 55 and 56, and provided with a feeding door 53. The first compartment 49 may be termed the softening compartment, the second compartment 50, is the flattening compartment, the third compartment '51, is the intermediate or lock compartment, and the-fourth compartment 52, is the annealing compartment. Through these compartments the glass cylinders are fed while each cylinder 39 is supported ait its upper portion by a bar 42 extending 'therethrough and projecting beyond each end. Each bar, previously heated before entering the compartment 49, has suitable lugs 40 and 41 on its upper s urface on which the cylinder initially rests, and which serve to prevent the contact of the coldglass along a generant line of the cylinder with the heated bar.

Each bar 42 forms a part of a flattening assembly. Each of` these assemblies also comprises a lower bar 47, projectinglongitudinally through the cylinder to beyond the ends thereof, and initially held out of contact with the bottom of the cylinder by a latch 48 at each end, the latches being pivoted to links 43, pendant from the upper bar and engaging a suitable projection on links 44 arising from the lower bar. The links 43 and 44 are also connected together by the toggle arms 45 and446, which in the initial position of the apparatus have the position shown in Figure 5. The links and levers thus constitute an expansible connection between the bars.

A cylinder having the described arrangement of the bars 42 and 47 contained within it is fed through the structure, while supported on the upper bar 42, first entering the means of burners 58 assumes under its own weight an ovate cross section, the bar 47 being held up by the latches 48. \Vhen the cylinder has become sufficiently heated, it is fed into the compartment 50. lVhile in this compartment, and at the position indicated by the section line 18-vl8, the lower bar 47 is lifted by means of' heads 61 on the vertical pistons 60, which may be raised from' the outside for this purpose. The lifting of' the bar 47 disengages the latches 48, so that when the pistons are again allowed to fall, the bar 47 will follow them down until arrested by the bottom of the now ovate glass. Under the weight of this har the glass, which is heated by means of' the burners 59, tends to further flatten until finally it consists of two flat sheets 62 connected by semi-circular portions 63. The dropping of the bar 47,'which accomplishes this, is 'accompanied by a straightening out of the levers 45- and 46, so that the pairs'of' lingers 64 (a pair being carried on the opposite sides of each lever) will l grasp the edges of the now flattened sheets and serve to guide the Same andhold them true. This is of importance as there is a tendency under certain conditions `for the edges of' the sheets to have a reentrant curve beneath the upper bar, and the inner fingers of opposite pairs thus act as separators to space the two sheets. The extent to which the lower bar may drop will be limited by the length of the levers 45 when straightened. The glass is now fed from the flatening compartment 50 to the lock compartment 51, and after the door is closed, the door 56 is opened, and the glass is fed into the annealing compartment 52. 1t will be seen that the doors 55 and 56 and the lock compartment prevent the annealing compartment from being in direct communication with the Hattening compartment 50, and hence permit better regulation of the temperature in the annealing compartment. The flattened cylinders are now fed through the annealing compartment and are 'finally removed therefrom. The flattening assembly may be now removed from the glass and the curved end portions thereof cut olf, providing two sheets, the flat- I tening assembly -being returned to the entrance end ot' the heating structure for further use.

Any suitable means may be provided for feeding the cylinders and their associated flattening assemblies through the heated structure. The mechanism shown for this purpose comprises two pairs of rodsl and 66, each pair consisting ofl a rod on each side of the heated structure, the pairs being independentlymovable longitudinally of' the heated strncture. The rods 65 are carried by rollers 67 working on tracks 69 located in the heating and flattening compartment, and the rods 66 are carried by rollers 68 workingon tracks 7 0, located in the annealing compartment.

Adjacent to each rod 65 and extending to l 56 is a longitudinal bracket 72, capable ot' being raised and lowered by the lever mechanism 74. t

A bar 42 of an expanding assembly, Such as descril'ied, with a cylinder of glass thereon, is placed on the rods 65 adjacent to the entrance door 53, as shown to the left of' Figure 16 and the rods are given a longitudinal lnotion into the heated Structure suliicient to transfer the cylinder to the position indicated by section line 17-l7, the bracket 7l being at this time down. If the bracket is now raised, the bar 42 will be transferredv to the bracket and the rods 65 may be withdrawn to their original poistion. Upon now lowering the bracket the bar 42 will be again transferred to the rods 65, but at a new poistion thereon. 'lhe nextstroke of the rods 65 will then move the cylinder into the flattening chamber and to the position ot' section line 18-18. 'lhe brackets 71. are nowagain lifted and lowered and the rods 65 are again moved out and in. The last stroke will carry the glass into the lock chamber, to the position indicated by the cross section 19-19. It will be understood I that during each of the reciprocations above described of the rods 65, a new cylinder will be placed upon the rods 65 and will be fed forward as hereinbef'ore described through the successive steps.

When the glass has been carried to the position indicated by section line 19-19, the brackets 71 and 72 are raised, the door 56 is lifted and the rods 65 are withdrawn to their original position. At the same time the rods 66 are given a longitudinal motion into the lock compartment 51. Upon now lowering the brackets 71 and 72, the bar 42 in cross line 19-19 will bev transferred to the rods 66. The rods 66 are now given'their feeding stroke v(which is shorter than the stroke of the rods 65), this stroke being sufficient to transfer the cylinder in the intermediate compartment to the annealing chamber and being equal to the desired spacing of tlieglass in the last named chamber. Then the door 56 is dropped. Upon successive be exerted at a proper time on the lowerbars 47.

Having thus described o ur invention what we claim as new and desire to .secure by Letters Patent is Y, Y

1. In an apparatus for forming flat glass sheets from a cy ,der of heated glass, the combination vwith a flattening assembly consisting of a pl sible connection between them,

of sheet separators interposed between thebars.

. Va heated structure,

2. In an apparatus for forming ilat glass sheets from a cylinder of heated glass, the combination with aiattening assembly consisting of a plurality of bar s with an extensible connection between them, of sheet separators interposed between the bars, and latches adapted to hold the bars together.

3. In an apparatus for forming ilat sheets from a cylinder of heated glass, the combination with a flattening assembly comprisinga plurality of bars with an extensible connection between them, of latches adapted to hold the connection in contracted position, and means for releasing the latches.

4. In an apparatus for forming llat sheets of glass from a cylinder of heated glass, the combination with a plurality of bars, pivoted levers forming an extensible connection between the bars, and sheet gripping fingers carried by the levers and placed upon the edges of the sheets formed from each cylinder by the straightening of the levers.

In an apparatus for forming flat sheets of glass from a cylinder of heated glass, the combination with a plurality of bars, pivoted levers forming an extensible connection between the bars, and sheet gripping fingers carried byV the levers and placed upon the edges of the sheets formed from each cylinder hy the straightening of the levers, and latches adapted to hold the connection contracted.

6. In an apparatus for forming flat sheets from a glass cylinder, the combination with a heated structure, of a flattening assembly, adapted to be inserted in the cylinder and consisting of an upper and a lower bar having anext'ensible connection, means for feeding the assembly with the glass thereon in an out of the structure, means forinitially holding the connection contracted, and means for releasing said holding means when the assembly is in the heated structure.

7 In an apparatus for forming flat sheets from a glass cylinder, the combination with adapted to be inserted in the cylinder and consisting of an upper and a lower bar havurality of bars with an exten-- of a flattening assembly ing an extensible connection, means for feed- 8. In an apparatus for forming flat sheets i from a glass cylinder, the combination with a heated structure, of a attening assembly adapted to be inserted in the cylinder and consisting of an upper and a` lower-.bar having an extensible connection by whichthey are connected, latches by 'which the connection is held contracted, and means located in the heated structure for releasing said latches. e

9. In an apparatus for forming Hat glass sheets from glass cylinders, the combination with a heated structure, comprising a flattening compartment, an annealing-compartment, and a compartment intermediate of the -two, the several compartments beingseparated from each other, a flattening assembly adapted to be inserted while contracted in a glass cylinder and together with thefglass to be sent through the structure,

and means within the flattening compartment to permit the liattening assembly to open.

l0. The hereinbefore described method of A producing flat glass sheets from a glass cylin- V der which comprises inserting a plurality of barsflongitudinally in the cylinder, the Vone above the other, adjacent to two opposite generant lines of the cylinder, restraining such bars from relative movement while the glass is cold, heating the cylinder and' releasing, when the cylinder is hot, the lower of sai bars for downward movement of a positively limited exten 12. The hereinbefore described method of producing flat glass sheets from a glass cylinder which comprises inserting a plurality-of` bars longitudinally in the cylinder, the one above the other, adjacentto two opposite generant lines of the cylinder, restraining such bars from relative movement while the glass is cold, heating the cylinder and releasing, when the cylinder is hot, the lower of said bars for downward movement, and limiting the approach of the two sheets thus formed. Y

13. The hereinbefore described method of producing flat glass sheets from glass cylinders, which .comprises inserting a plurality when the cylinder is hot, the lower of bars longitudinally in the cylinder, the one above the otherLsupporting the cylinder on and transporting it by the upper of said bars through zones of softening and.

annealing temperatures, restraining the lower bar from downward movement while the cylinder is cold, and releasing it for llownward movement when the cylinder is 14. The hereinbefore described method of producing flat glas 'sheets from glass cylinders, which comprises inserting a plurality of bars longitudinally in the cylinder, the one above theI other, supporting the cylinder on and transporting it by the upper of said barsfthrough zones of softening and annealing temperatures, restraining the lower bar from downward movement while the cylinder is cold, and releasing it for a positively limited downward movement when the cylinderis hot.

15. In an apparatus for forming glass sheets from a cylinder of heated glass, the combination with a supporting -bar located longitudinally within the cylinder and having 'separated lugs on its upper surface on which the cylinder is carried, and an extending bar located longitudinally within the cylinder and carried by the bottom portion thereof.

In testimony whereof we hereunto arix our signatures.

JULES ARRAULT. V-LHCIEN DESCHAMPS. 

